苹果树更新修剪对土壤水分及树体生长的影响

在渭北高原以苹果树长放修剪为对照,监测盛果末期苹果树更新修剪对果园0～500cm土层土壤水分及树体生长状况的影响。结果表明:更新修剪的果园0～240cm土层土壤水分极显著高于长放修剪,240cm土层以下土壤水分与长放修剪无显著差异;更新修剪的果园土壤水分蒸散高峰较高且延迟30d左右,但生长期的平均蒸散强度与长放修剪无显著差异;更新修剪的苹果树翌年新梢总数显著减少,短枝、叶丛枝比例显著降低,中枝、长枝比例显著增加,单果质量、果实产量、经济产值和水分产出率显著提高,但耗水量与长放修剪无显著差异。综上可见,更新修剪改良了果园的土壤水分状况,促进了树体生长,是渭北高原盛果末期苹果树的适宜修剪方法。

Effects of renewal pruning on soil moisture and growth of apple tree

Compared with long-branch pruning of apple tree in Weibei Plateau of Shaanxi Province,the effects of renewal pruning on soil moisture in 0-500 cm soil depths and the growth of apple tree at final full productive stage were determined.The results showed that soil moisture in 0-240 cm depths was significantly increased by renewal pruning,and soil moisture below 240 cm soil layer had not significant difference between renewal pruning and long-branch one from sprout stage to defoliation stage.The peak of soil evapotranspiration intensity by renewal pruning was higher and delayed 30 d than that by long-branch one,but the average intensity had not significant difference between renewal pruning and long-branch one during the growth period of apple tree.Renewal pruning reduced significantly the total number of branches per tree in next year,the proportion of short and foliage branches,and increased significantly the proportion of long,medium branches.Meanwhile,renewal pruning increased significantly fruit yields and fruit mass,improved significantly orchard economic value and water output ratio,but had not significant difference in water consumption compared with long-branch pruning.As a result,renewal pruning improve soil moisture and promote growth of apple tree,which is an appropriate pruning method for apple tree at final full productive stage in Weibei Plateau of Shaanxi Province.